Gun type oil burner



March 8; 19 D. L. GETZ ET AL GUN TYPE OIL BURNER 3 Sheets-Sheet 1 Filed 001;. 4, 1950 DELMOND L. GETZ 4*} ROBERT O. HEDGES ATTORN EYS March 8, 1955 D. GETZ ET AL 2,703,608

GUN TYPE OIL BURNER Filed 061;. 4, 1950 3 Sheets-Sheet 2 DELMOND L. GETZ 3546 ROBERT O. HED GE ATTORNEYS March 8, 1955 D. GETZ EI'AL 2,703,608

GUN TYPE OIL BURNER Filed Oct. 4, 1950 3 Sheets-Sheet 3 DELMOND L. GETZ 6, ROBERT o. HEDGES ATTO R N EYS United States Patent GUN TYPE OlL BURNER Delmond L. Getz and Robert O. Hedges, Springfield,

Ohio, assignors to The Steel Products Engineering Company, Springfield, Ohio, a corporation of Ohio Application October 4, 1950, Serial No. 188,448

7 Claims. (Cl. 158-76) This invention relates to oil burners for heating purposes and the like, and more particularly to oil burners adapted for domestic installation for conversion use.

The invention has special relation to the control of the air flow to and through the combustion head of an oil burner, with the objective of increased uniformity and efficiency of combustion as well as ease of servicing and adjustment in accordance with desired operating conditions. The invention is accordingly directed in part to the elimination of restrictions to air flow inside the blast tube of the burner in order to obtain a more uniform and efiicient flow of air through the blast tube, and also to the control of the air flow direction and its velocity close to the point of origin of the atomized oil spray.

It is accordingly one of the principal objects of the invention to provide a combustion head for an oil burner in which a tubular air controlling member is constructed for cooperative action with the blast tube and the outer air cone to effect zoning of the air supply into a low velocity stream adjacent the oil nozzle and at the center of the atomized oil spray and a high velocity stream in a swirling direction around the tip of the nozzle and into the outer portion of the oil spray.

Another object is to provide an oil burner wherein the tubular air controlling member of the combustion head includes bafile and deflector portions which cooperate to control the direction of flow of the primary air in angular relation with the oil spray from the nozzle such that intimate intermixing of the oil and air is obtained at a position closely adjacent the nozzle to give improved shape to the flame without requiring positioning adjustments of the combustion head for different settings of the control for the inlet of the air supply.

An additional object is to provide an oil burner having the combustion head mounted in the blast tube in such manner as to be easily removable as a unit for inspection, adjustment or other servicing without requiring disassembly or dismantling of other parts of the burner.

It is also an object of the invention to provide an oil burner wherein the air inlet to the blower includes a readily adjustable damper member of symmetrical shape which gives even distribution of the flow of air to the blower wheel and which is symmetrically adjustable without reducing the overall effective capacity or width of the blower wheel.

Other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.

In the drawings- Fig. l is a somewhat diagrammatic perspective view of an oil burner in accordance with the invention, with portions broken away to illustrate details of internal construction and arrangement;

Fig. 2 is a rear elevational view of the oil burner with portions broken away;

Fig. 3 is an enlarged fragmentary view showing the adjustable air inlet mechanism for the blower of the oil burner, the view being in section approximately on the line 33 of Fig. 2;

Fig. 4 is a detail view of the air inlet mechanism taken at right angles to Fig. 3 approximately on the line 44 of Fig. 3;

Fig. 5 is a fragmentary view illustrating the operation of adjusting the air inlet mechanism of Figs. 3 and 4;

Fig. 6 is a fragmentary view of the wire ring for preventing accidental insertion of the fingers into contact with the blades of the blower;

- her.

Fig. 7 is a detail view in vertical section through the blast tube of the burner to show the combustion head;

8 is a fragmentary section on the line 8-8 of 1g.

Fig. 9 is an end elevation looking from left to right in Fig. 7;

Fig. 10 is a view of the front end of the combustion head, with a portion thereof and of the air controlling cone therein broken away;

Fig. 11 is a detail view in section on the line 1111 of Fig. 12 showing the inner air controlling tubularmemher with the swirl fins removed; and

Fig. 12 is a detail view of the rearward end of the air controlling member of Fig. 11, looking from left to right in Fig. 11.

Referring to the drawings, which illustrate a preferred embodiment of the invention, Figs. 1 and 2 show the general construction of an oil burner of the high pressure or pressure-atomizing type adapted for conversion use in domestic installations. This burner is' shown as including a main housing 15 provided with a pedestal type supporting base 16 having adjustable leveling feet 17 and a sheet metal cover 18. A motor 19 and an oil pump assembly 20 are symmetrically mounted at either side of the housing 15, the pump assembly having a removable sheet metal cover 21. The housing 15 encloses a blower wheel 22 having its hub 23 mounted on the motor shaft 24, and a flexible coupling 25 connects the hub 23 with the drive shaft 26 of the oil pump 20. The air inlet casting 30 for the blower wheel is secured to the housing 15 by means of bolts 31 extending through the projections 32 on the casting, and the housing 15 includes a curved portion 33 which provides the air inlet opening to the interior of the blower wheel. The oil pump 20 is in turn mounted on the outer end of the inlet casting 30 by means such as bolts 35.

The adjustable air inlet damper for the blower wheel 22 is shown in detail in Figs. 2 to 6. A tubular housing is pressed into the air inlet casting 30 at 41 and encloses the coupling 25. A conical damper 42 includes a hub portion 43 slidably mounted on this housing 40 to control the effective flow area through the radial openings or ports 44 in the inlet casting 30 to the blower wheel. A spring clip 45 is mounted on the hub 43, and its arm portions extend through slots 46 in the hub for frictional engagement with the outer surface of the housing 40 to hold the damper 42 in axially adjusted position on the housing 40. A wire 47, having its ends secured together by the clip 48 as shown in Fig. 6, extends around the periphery of the inlet casting 30 to reduce the width of the air ports 44 to a dimension preventing accidental insertion of the fingers into contact with the blades of the blower Wheel.

This damper unit is readily adjusted manually as illustrated in Fig. 5. As shown, screw drivers or similar pointed tools are readily insertible through the openings in the casting 30 for engagement with the end of the damper 42 to slide the damper along housing 40 against the friction of the spring 45. Since this damper is symmetrical in shape and acts to regulate uniformly the effective flow area through the ports 44 to the blower wheel 22, it will be seen that there is at all times a uniform and symmetrically distributed flow of air to the blower for supply to the combustion head of the cham- This damper construction also tends to prevent indiscriminate dampering or bumping, causing changes in air supply during operation, since the damper must be positively shifted against its spring holding means in order to change the setting thereof.

The combustion head of the burner is shown in de tail in Figs. 7 to 12. It includes an oil nozzle 50 mounted on the forward end of the oil tube 51, which is detachably connected at 52 with the oil outlet line 53 from the oil pump 20, the inlet tube which conducts the oil to the oilpump from the supply tank (not shown) being indicated at 54. The nozzle 50 is supported within a tubular air controlling member 55 of the combustion head, which lies just within the outer end of the blast tube 56, and this member 55 acts to zone the air flow from the blower wheel into inner and outer annular streams past the nozzle. An outer air cone 57 is secured within the outer end of the blast tube as shown in Fig. 7, and the inner end of the blast tube is secured within the open portion 58 of the housing 15 by attaching screws 59 as shown in Fig. 7. The member 55 is provided with swirl blades 60 on its outer surface which lie in the annular space between the member 55 and the blast tube 56, and the forward tips of these blades abut the inner end of the outer air cone 57.

The air controlling member 55 is held in position centrally of the blast tube by a multi-armed bracket 65 of generally Y-shape which also supports the oil tube 51 and the electrodes 66 for igniting the fuel discharged from the nozzle 50, the electrodes being secured to the bracket by means of clamps and bolts as indicated at 67. The cables 68 for the electrodes are supported on the oil tube 51 by a spacer 70, and they are provided with releasable clips 71 for connection to an ignition transformer 72 mounted on the housing 15 below the motor 19. symmetrically mounted on the other side of the housing from the transformer is a primary combustion control unit 75 provided with a removable cover 76, and a reset button 77 is provided in the cover 76 to reset the primary combustion control in case of a safety shutdown of the burner unit.

This combustion head assembly is removable as a unit from the blast tube upon removal of the cover plate 80 at the rear of housing 15, which is secured to the housing by screws 81. The bracket 65 is secured to the oil tube 51 by a U-shaped clamp 83 and clamping screw 84 as shown in Fig. 8. The tube 51 is in turn secured with respect to housing 15 by means of a bracket or adapter 85 mounted on the right angled rearward end portion of tube 51 by a set screw 86 and attached by screws 87 to a boss portion 88 of the housing. Thus after removal of the cover plate 80, it is only necessary to loosen the screws 87, disconnect the clips 71 from transformer 72 and disconnect the oil line 53 from tube 51 at 52, whereupon the combustion head assembly can be withdrawn as a unit from the blast tube through the back of housing 15.

The air controlling member 55 is shown in detail in Figs. ll and 12, and it is cylindrical over a major portion of its length. At its rearward end the member 55 is provided with a crescent shaped baflle 95 which acts to meter the air flowing directly past and closely adjacent the outlet of nozzle 50, and particularly along the lower side of the nozzle, the bafile 95 being readily welded to the member 55 and to the forward end portions 96 of bracket 65. The front end portion 99 of member 55 includes a frusto-conical section which is cut back as shown at a relatively sharp angle to the vertical, for example an angle of about This forward end portion of the member 55 thus forms a generally oval opening as viewed axially of the member, with the tapered portion 99 forming a hood-like deflector which cooperates in operation with the baffle 95 to deflect the air stream passing through the member 55 downwardly toward the bottom of the combustion chamber, the member 55 being maintained in proper postion with its portion 99 uppermost by the connection of bracket 65 to the oil tube 51 and the connection of tube 51 to the main housing as described. The resulting control over the direction and pattern of the air flow gives improved mixing of the air with the oil spray and imparts an improved shape to the flame without requiring positioning adjustments of the combustion head for changed settings of the inlet air damper 42.

The air controlling member 55 is readily formed from sheet metal, and it is found that this construction makes possible the use of relatively shallow angular swirl blades 60, which are similarly formed of sheet metal and readily welded to the member 55. These blades cooperate in operation with the outer air cone 57 to effect intimate intermixing of the high velocity outer flow of air with the oil spray at a position relatively close to the nozzle, which promotes a soft flame for efficient combustion.

It will thus be seen that the battle 95 and the member 55 thus cooperate to form composite baflie means cooperating with the blast tube to zone the air supply from the blower wheel into a high velocity swirling air stream in the passage between the member 55 and blast tube which is deflected symmetrically toward the nozzle by means of the outer cone 57, a relatively high straight line velocity flow through the upper part of the member 55 which is deflected downwardly towards the point of combustion by means of the hoodlike portion 99 on member 55, and a low velocity stream adjacent and below the nozzle which results essentially from only the static pressure within member 55 since the velocity pressure of the air in this area is checked by the bafile plate 95. In addition, it will be noted particularly in Figs. 7 and 9 that the compact and simplified construction of the combustion head assembly provides minimum restriction in the path of air flow through the blast tube, which further aids in the desired quiet and eflicient operation of the burner.

It will accordingly be seen that the invention provides highly effective and eflicient control over the air supply for the oil burner as well as simplified maintenance of the burner. The air inlet construction assures that the air supply to the blower wheel is at all times evenly and symmetrically distributed, and it also assures that the full effective width of the blower wheel is employed in all adjusted positions of the inlet. Moreover the adjustment of the inlet is simple while at the same time requiring positive action, and indiscriminate or accidental dampering is thus effectively prevented. Similarly the construction of the combustion head promotes maximum uniformity of distribution of air flow to the nozzle as well as case of removal of the head assembly for servicing without requiring careful readjustment, and in addition the air cone construction imparts improved operating characteristics to the flame for efiicient combustion.

This application is a continuation in part of our application Serial No. 2,713 filed January 16, 1948, and assigned to the same assignee as this application, now Patent No. 2,632,499 issued March 24, 1953.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. An oil burner of the character described comprising a combustion head including a nozzle having a discharge outlet, means for supplying liquid fuel to said nozzle for discharge through said outlet, a tube surrounding said nozzle, a tubular member mounted between said nozzle and tube and of substantially lesser diameter than said tube and substantially greater inner diameter than said nozzle to define inner and outer annular through pas sages extending axially of and surrounding said nozzle, means for supplying a flow of air to said tube for discharge through said passages, and a baffle of not more than approximately one-half the effective flow area of said tubular member partially closing the rearward end of said tubular nozzle below said nozzle while leaving the remainder of said member open for through flow of air to limit the amount of said through air flow passing through said inner passage adjacent said nozzle outlet.

2. A combustion head for use in an oil burner having a nozzle for discharging an atomized fuel spray, comprising a blast tube surrounding said nozzle, a tubular member of cylindrical cross-section adapted to receive said nozzle therein and of greater inner diameter than said nozzle and of lesser outer diameter than said blast tube, said member having an inwardly tapered portion at the front end thereof, said tapered portion being cut back at a relatively sharp angle to the vertical to impart an oval shape to the opening at the front end of said member with said tapered portion forming a hood-like deflector portion overhanging said opening, and means mounting said member in fixed angular relation to said blast tube to locate said member with said deflector portion uppermost for directing the air stream flowing through said member downwardly toward said atomized spray.

3. A combustion head for use in the blast tube of an oil burner having a nozzle within said blast tube for discharging an atomized fuel spray, comprising an annular member of cylindrical cross-section adapted to receive said nozzle therein, a baflle located at the rearward end of said member for metering the air flowing therethrough, said member having an inwardly tapered portion at the front end thereof, said tapered portion being cut back at a relatively sharp angle to the vertical to impart an oval shape to the opening through the front end of said member and with said tapered portion forming a hood-like deflector portion overhanging said opening and diametrically opposed to said baffle, and

- means for mounting said member in fixed angular relation to said blast tube to locate said member with said deflector portion uppermost for directing the air stream flowing through said member downwardly toward said atomized spray.

4. A combustion head for use in an oil burner having a nozzle for discharging an atomized fuel spray, comprising a blast tube surrounding said nozzle, a tubular member of cylindrical cross-section adapted to receive said nozzle therein and of greater inner diameter than said nozzle and of lesser outer diameter than said blast tube, said member having an inwardly tapered portion at the front end thereof, means for positioning said member centrally of said blast tube to provide an annular space between said member and the inner surface of said blast tube, swirl blades located in said annular space to impart a swirling direction to the air flow therethrough, said tapered portion of said member being cut back at a relatively sharp angle to the vertical to impart an oval shape to the opening at the front end of said member with said tapered portion forming a hood-like deflector portion overhanging said opening, an outer air cone at the outer end of said blast tube for directing said swirling air toward the center of said atomized spray, and means for mounting said member in fixed angular relation to said blast tube and axially inwardly of said outer air cone to locate said member with said deflector portion uppermost for directing the air stream flowing through said member downwardly toward said atomized spray.

5. In an oil burner including a main housing having a blast tube supported thereon, the combination of an oil tube adapted to be received within said blast tube, a nozzle on the front end of said oil tube for discharging an atomized spray, a tubular member of lesser diameter than said blast tube forming a combustion head for receiving said nozzle therein, a multi-armed bracket secured to said a tubular member with the arms thereof in engagement with the wall of said blast tube'to locate said head in centered position within said blast tube, electrodes for effecting ignition of the oil spray from said nozzle, means for securing said electrodes to said bracket for support thereby, means for forming an adjustable connection between said bracket and said oil tube and providing for relative adjustment of said combustion head and said oil tube lengthwise of said blast tube to locate said combustion head in predetermined relation to said nozzle, and means for releasably securing said oil tube in fixed relation with said housing to locate said combustion head and nozzle in predetermined relation with the outer end of said blast tube while providing for removal of said oil tube with said nozzle and combustion head as a unit through the rearward end of said blast tube.

6. An oil burner of the character described comprising a combustion head including a nozzle having a discharge outlet, means for supplying liquid fuel to said nozzle for discharge through said outlet, a blast tube surrounding said nozzle, a tubular member mounted between said nozzle and blast tube to define inner and outer annular passages substantially concentric with said nozzle, means for supplying a flow of air to said blast tube for discharge through said passages, swirl blades mounted in said outer passage for imparting a swirling action to the air flow through said outer passage, a baffle located at the rear end of said tubular member below said nozzle and of smaller efiective area than said tubular member to effect substantial blocking of the flow of air through said tubular member below said nozzle while leaving open the upper portion of said tubular member for straight through flow of air above said nozzle, and cone means supported at the outer end of said blast tube for directing saliad swirling air flow towards the center of said blast ttl e.

7. An oil burner of the character described comprising a combustion head including a nozzle having a discharge outlet, means for supplying liquid fuel to said nozzle for discharge through said outlet, a blast tube surrounding said nozzle, a tubular member mounted between said nozzle and blast tube to define inner and outer annular passages substantially concentric with said nozzle, means for supplying a flow of air to said blast tube for discharge through said passages, swirl blades mounted in said outer passage for imparting a swirling action to the air flow through said outer passage, a baflle located at the rear end of said tubular member below said nozzle and of smaller eifective area than said tubular member to effect substantial blocking of the flow of air through said tubular member below said nozzle while leaving open the upper portion of said tubular member for straight through flow of air above said nozzle, said tubular member being of substantially circular section over the major portion of the length thereof and having the forward end thereof inwardly tapered, said tapered portion being cut back at an angle to the length thereof imparting an oval shape to the opening therethrough and with said tapered portion forming a hood-like deflector portion overhanging the front end of said tubular member to deflect downwardly said through air flow, and cone means supported at the outer end of said blast tube for directing said swirling air flow towards the center of said blast tube.

References Cited in the file of this patent UNITED STATES PATENTS 1,955,852 Lattner Apr. 24, 1934 1,971,246 Anderson Aug. 21, 1934 2,066,806 Smith et a1 Jan. 5, 1937 2,078,021 Rodler Apr. 20, 1937 2,098,455 Lattner Nov. 9, 1937 2,163,915 Reif et al June 27, 1939 2,221,519 Jones et a1. Nov. 12, 1940 2,395,487 Logan Feb. 26, 1946 2,451,964 Logan Oct. 19, 1948 2,473,769 Schinman June 21, 1949 2,485,244 Sanborn Oct. 18, 1949 2,585,081 Bernhard Feb. 12, 1952 2,531,538 Smith Nov. 28, 1950 

